5.1. Merits

Try these first

1. 1.

   What is the main refrigerant used in air refrigeration systems?

   Hint

   Think about what is freely available and safe.

2. 2.

   Name one advantage of using air as a refrigerant.

   Hint

   Consider the environmental impact of refrigerants.

3. 3.

   What is the coefficient of performance (COP) in refrigeration?

   • Efficiency measure
   • Performance measure
   • Cost measure

   Hint

   Remember how the performance of refrigeration systems is evaluated.

4. 4.

   True or False: The Bell-Coleman cycle is commonly used in aircraft.

   • True
   • False

   Hint

   Consider where air refrigeration is applied.

5. 5.

   Evaluate the efficiency factors of the Bell-Coleman cycle compared to standard vapor-compression systems under varying environmental conditions.

   Hint

   Compare operational environments and their impacts on energy consumption.

6. 6.

   Design an air refrigeration system for a hypothetical aircraft, detailing your component choices and justifying them with respect to the system's merits.

   Hint

   Reflect on the specific needs of aircraft such as temperature control and passenger comfort.